There have conventionally been image readers in which X-ray photography is performed by using an imaging plate formed by applying a photostimulable phosphor on a support, X-ray absorption distribution of a subject accumulated in the imaging plate as a latent image is read out as X-ray image information, and the read-out image data are erased. For example, Non-patent document 1 discloses an image reader to be set up on a predetermined site and used. This image reader is connected to an electric socket provided on a wall surface of an X-ray room or the like, and driven with an alternating current.